SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fd37bef524951a46af63a3519ce12a0427ac5177dbdee19b8389151c0747e642' 
  AND token = 'XTrwEKZhuzR4Wv0zdLZGRKHKq8DVO6NbdxOUEvRnh6g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}